We have previously shown that determination of glucose uptake using ${alpha}$-methylglucose(${alpha}$-MG) is very sensitive and rapid parameter for the assessment of loss of cellular fu nction in renal cell line($LLC-PK_1$). The present study was designed to elucidate the mechanism of inhibition of ${alpha}$-MG uptake and the intracellular site of toxic action of cisplatin(CIS). $LLC-PK_1$ cells were exposed to various concentrations(5 ${mu}$M-l00 ${mu}$M) of CIS for 5 hrs or 24 hrs and ${alpha}$-MG uptake was determined. Mitochondrial function was evaluated by measuring intracellular ATP content and MTT reduction. The activities of marker enzymes for the basolateral membrane(Na$^+$-K$^+$ ATPase) and brush border membrane (alkaline phosphatase: ALP) were also measured. CIS treatment significantly inhibited the ${alpha}$-MG uptake in a time- and dose-dependent manner above 25 ${mu}$M for 5 hrs. Intracellular ATP content and MTT reduction were affected by 24 hr-treatment of 50 ${mu}$M CIS. The activities of Na$^+$-K$^+$ ATPase and ALP were significantly decreased at 10 ${mu}$M and 5 ${mu}$M of CIS for 24 hrs, respectively. The incubation with CIS for 5 hrs had no effects on the intracellular ATP content, MTT reduction and the activities of marker enzymes up to 100 ${mu}$M. These results partly indicate that inhibition of ${alpha}$-MG uptake by CIS may not be attributed to the disturbance of mitochondrial function or inhibition of the activity of Na$^+$-K$^+$ ATPase and can be resulted from direct effect of CIS on the Na$^+$/glucose cotransporter in brush border membrane. This study shows that additional mechanistic information, indicating the intracellular site of nephrotoxic action, can be gained by coupling the ${alpha}$-MG uptake and ATP content or the activity of Na$^+$-K$^+$ ATPase.